Climate Change - Greenhouse Gases and the Greenhouse Effect

Greenhouse gases are responsible for the Greenhouse Effect. But before we investigate that, let’s find out what greenhouse gases are. Can you name any of them?

The most well-known greenhouse gas is Carbon Dioxide, also known as CO2. Other greenhouse gases are methane, carbon monoxide, sulphur dioxide, nitrous oxide and water vapour.

But greenhouse gases are not always bad. We actually need  greenhouse gases in the atmosphere in order for life on Earth to exist:

- Trees and plants would not survive without CO2 as they need it for photosynthesis.
- The plants in turn provide food for animals and humans and they give out oxygen for animals to breathe.
- Greenhouse gases also keep the planet warm enough for life to exist. 

Without them the world would be 33°C colder than it is now and life would not be possible (the average temperature for November in the UK is around 6°C. This means it would be more like –27°C here instead). This is because the greenhouse gases form a protective layer in the atmosphere that stops all the sun’s warmth disappearing back up into space.

So why are they thought of as bad?
The trouble now is that the concentration of greenhouse gases in the atmosphere is increasing to a level that has not been seen for millions of years and this is changing the world’s climate.

The greenhouse effect means that in general, the planet is getting hotter. But in some places around the world it is also getting wetter; some are getting drier (the Sahara desert is expanding and it is likely that this will continue due to climate change) and others are getting windier. So it depends on where you live as to what effect climate change may have on you:

- The Inuits in the Arctic regions have noticed the ice melting more in the summer months and freezing less in the winter months.
- The Shanty towns in Asia and Latin America are suffering more floods and storms than in the past.
- The Europeans are witnessing more forest fires, melting glaciers and heat waves than ever before. Many locations in England experience hose pipe bans in the summer.